Items | Pipelines | Metallographic structure | Figures | Hardness values |
1# | P1603-4 | Austenite plus precipitated phases, the precipitated phases are granular, banded, and chain-like. | Figure 2 | 150, 154 and 154 |
2# | P10615-4 | Austenite plus precipitated phases, the precipitated phases are granular, banded, and chain-like. | 141, 144 and 145 | |
3# | P10702-1 | Austenite plus precipitated phases, the precipitated phases are granular, banded, and chain-like. | 150, 145 and 141 | |
4# | P10705-2 | Austenite plus precipitated phase, the precipitated phase is granular. | 156, 158 and 154 | |
5# | P10705-2 | Austenite plus precipitated phase, the precipitated phase is granular. | 143, 145 and 146 | |
6# | P10712-3 | Austenite plus precipitated phase, the precipitated phase is granular. | Figure 3 | 149, 150 and 160 |
7# | P10712-2 | Austenite plus precipitated phase, the precipitated phase is granular. | 135, 139 and 140 | |
8# | P10712 (elbows) | Austenite plus precipitated phase, the precipitated phase is granular. | 130, 125 and 137 | |
9# | P10611 | Austenite plus precipitated phase, the precipitated phase is granular. | 160, 185 and 182 | |
10# | P20412-1 | Austenite plus precipitated phase, the precipitated phase is granular. | 141, 145 and 150 | |
11# | P10611-1 | Austenite plus precipitated phase, the precipitates are distributed in granular, banded, and chain shapes, and there are suspected cracks around the precipitates. | Figure 4 | 141, 150 and 139 |
Items | C | Si | Mn | P | S | Cr | Mo | Ni | Cu | Fe |
Average values | 0.081 | 0.85 | 1.43 | 0.036 | 0.0035 | 18.03 | 0.065 | 8.015 | 0.330 | 70.21 |
Standard values | 0.080 | 1.00 | 2.00 | 0.050 | 0.0300 | 18.8-20.0 | / | 8.0 to 11.0 | / | / |